Free cellular communication

There's a way to transfer data between two smartphones with apps that call and hangup each-other without answering. And with zero charge by the carriers.

Cellular roaming fees are scandalous. I'm sure, one day, our offsprings will be mind-boggled when we tell them that we paid more than a dollar to send a few bytes across countries.

The app I'm suggesting can also be used for free local texting.

The side that sends the data initiates the calls, a two second ring means "0", and a four second ring means "1". Notice that usually there's no charge when there is just a ring, if the receiving side doesn't answer.

The app that is receiving the rings notes each ring as a bit of a binary value. After a few dozen rings it converts the message to ASCII text and shows it to the user.

This way of communication might be slow, but a more efficient system can be engineered using more bits, 3 second, 5 second rings and so on.

Business class seats lottery

Most flights I take, I see more than 50% of the business class seats vacant.
Traveling companies should have a lottery for passengers, while on board, for those vacant seats. They can also advertise it: "fly with us and you might get a free business class upgrade!".
This will not demotivate business travelers from actually buying fully priced business class seats in advance. Trust me, they will not bet their 10 hour flight which they frequent, business class travelers will pay close to anything to make their flight a little more comfortable, you would too, if you traveled 3 times a week and could deduct the cost from your taxes.